According to nutritional data from the US Department of Agriculture (USDA), longans contain quite high levels of carbohydrates and natural sugars. Because of their easy-to-eat sweetness, many people tend to eat too much at once without realizing that their sugar intake is increasing sharply. This is the most common mistake.
Eating too much longan in a short time can quickly increase blood glucose, especially in people at risk of pre-diabetes or type 2 diabetes.
A study published in Frontiers in Nutrition emphasizes that excessive consumption of high-sugar-carrying fruits can still affect blood sugar control if the total diet is not balanced.
The second mistake is eating longan when too hungry. Longan has relatively high levels of fructose and glucose, so eating it on an empty stomach can cause blood sugar to rise rapidly and then drop suddenly, causing feelings of fatigue, burning or scratching in some sensitive people.
Eating a lot of longans in the evening is also not recommended a habit. According to nutrition experts, high sugar content from longans, if consumed near bedtime, can increase excess energy, affect metabolism and contribute to weight gain if prolonged.
Some studies also show that eating too much sweet food at the end of the day is associated with glucose metabolism disorders and poorer sleep quality.
Another fairly common mistake is believing that longan is blood-boosting, so the more you eat, the better. In fact, longan contains vitamin C and some minerals, but is not a food to treat anemia. Abusing sweet fruits for the purpose of "boosting" can inadvertently cause the body to have excess energy and increase blood sugar.
Some people also have a habit of drinking longan juice or using dried longan regularly.
Dried fruits are often higher in sugar and calories due to significantly reduced water content. This makes the risk of increased blood sugar and weight gain higher if eaten excessively.
The fifth mistake is combining longans with too many other sweet foods such as sweet soup, milk tea, condensed milk or syrup. Not only the individual sugar content but also the total sugar content of the whole meal is a factor that strongly affects metabolic health.
However, longan is not a harmful fruit. When eaten in moderation, longan still brings many benefits thanks to containing vitamin C, polyphenols and antioxidants.
